The present invention relates to a connector for industrial computers, and more particularly to a sectional connector substituting for conventional PC104 and PC104 PLUS industrial computer connectors, so that such conventional connectors may be formed by assembling a main connector having two rows of pins and at least two sub-connectors each having one row of pins through coupling means correspondingly provided on the main connector and the sub-connectors. The number of the sub-connectors in the sectional connector may change depending on actual need in designing the industrial computer, and easy and firm connecting and soldering of the pins to a printed circuit board row by row is possible with the sectional connector.
Computer-related technologies have been prosperously developed in the world. Computer manufacturers keep researching, developing and improving various kinds of computer-related components, from a simple screw to a high-power central processing unit (CPU), in attempts to upgrade the quality of computers and reduce the manufacturing cost to be competitive in the international markets.
Computers are usually differently designed to meet actual needs in different fields. For example, an industrial computer requires a CPU that needs not to operate at high speed but to work stably in compliance with preset steps to achieve a projected productivity. The Institute of Electrical and Electronic Engineers (IEEE) has established some basic standards for industrial computers and connectors for connecting buses. The main purposes of these standards for connectors are to enable automatic permutation, stack, and employment of connectors in computer designs and to reduce number of coupling elements in the motherboard.
A connector corresponding to PC104 specification is typically used to connect general buses and is an assembly of a connector having total 64 pins in two rows and a connector having total 40 pins in two rows. A connector corresponding to PC104 PLUS specification is typically used to connect high-speed Peripheral Component Interconnect (PCI) buses and is an assembly of a connector having total 64 pins in two rows, a connector having total 40 pins in two rows, and a connector having total 120 pins in four rows. When the conventional PC104 or PC104 PLUS connector assembled from at least two connectors is inserted onto a printed circuit (PC) board, the numerous pins in so many rows cause difficulty in soldering the pins to the PC board to result in high labor and time costs, making the PC104 and PC104 PLUS connectors not economical for use.
FIG. 1 is a partially sectioned side view showing the soldering of a conventional connector 1 having pins 11 in four rows to a PC board 2. As shown in FIG. 1, the connector 1 is connected to the PC board 2 by extending the pins 11 through holes 21 on the PC board 2 and then spot soldering each joint of the pin 11 and the hole 21 with a solder iron (not shown) and tin solder 3. It is most preferable the tin solder molten around each hole 21 finally forms a volcanic shape, so as to avoid poor contact between the hole 21 and the pin 11 due to cold or hollow soldering. However, it is obviously a time and labor consuming and highly difficult technical work to spot solder pins 11 in more than two rows. For example, the connector 1 has total 64 pins in four rows. It is easy to solder the pins 11 in two outer rows but not the pins 11 in two inner rows. A solder iron might be too thick to pass clearances among the pins 11 to perform the soldering. Moreover, the solder iron in high temperature would very possibly adversely affect the tin solder 3 that has been previously soldered around the holes 21 to cause cold and hollow soldering and/or short circuit between two pins 11.
To overcome the problem of difficult spot soldering on the connector 1 having a plurality of pins 11 in too many rows, there is developed a soldering tin sheet 4 having a plurality of through holes 41 corresponding to the pins 11 of the connector 1 to replace the spot soldering. As can be seen in FIG. 2, the pins 11 of the connector 1 are extended through the holes 41 on the soldering tin sheet 4 and the holes 21 on the PC board 2, and a hot blast heater (not shown) is used to blow at the soldering tin sheet 4 to and fro, so that the soldering tin sheet 4 melts at joints of the pins 11 and the holes 21. For a PC board 2 having surface-mounting devices (SMD), such tin-melting with a hot blast heater over a large area tends to cause not only cold soldering, hollow soldering, and short circuit between pins 11, but also undesired melting of tin solder at initially soldered electronic devices. When the molten tin solder at the previously soldered electronic devices become set again, it would result in the problems of cold soldering, hollow soldering, and short circuit between pins.
As shown in FIG. 4, the connector 1 has a bottom recess 12 in which the pins 11 are provided. The recess 12 defines a space between the connector 1 and the PC board 2. For the pins 11 and the holes 21 to fully connect at their joints, a layer of tin solder 3 is applied on the surface of the PC board 2 facing the recess 12, and a washer 5 as shown in FIG. 3 is mounted around each pin 11 in the recess 12, and finally, a hot blast heater is used to blow at the tin solder layer 3 to and fro, so that the tin solder 3 melts at the joints of the holes 21 and the pins 11. As mentioned above, such melting of tin solder over a large area tends to result in serious cold soldering, hollow soldering, and short circuit between pins, particularly in an invisible space. Thus, the problems existing in the conventional connector 1 are not overcome at all.
In FIGS. 5, 6 and 7, there is shown another type of conventional connector 1, pins 11 of which have a uniform width at all portions except for a small length at roots of the pins 11 that is wider than other portions. When the another type of conventional connector 1 is inserted onto the PC board 2 by extending the pins 11 through the holes 21, the widened roots of the pins 11 are stopped before the holes 21 and must be forced into the holes 21 by applying a pressure on the connector 1, so that the connector 1 is completely tightly associated with the PC board 2. It is known that the connector 1 is used to detachably connect buses. The above-described manner of forcing the connector 1 onto the PC board 2 would possibly cause undesired separation of the buses from the connector 1.
It is therefore desirable to develop an improved connector to substitute for the conventional PC104 and PC104 PLUS industrial computer connectors to solve the problems in soldering the pins of the connectors to the PC board.
A primary object of the present invention is to provide a sectional connector substituting for conventional PC104 and PC104 PLUS industrial computer connectors to enable easy and firm connecting and soldering of pins of the connector to a PC board.
Another object of the present invention is to provide a sectional connector for industrial computer that includes a main connector and a plurality of sub-connectors, the number of which is dependent on actual needs in designing industrial computers, connected to one another through coupling means provided on contact surfaces between two adjacent main connector and sub-connector or two adjacent sub-connectors.
A further object of the present invention is to provide a sectional connector for industrial computer that has completely even and smooth outer surfaces after being assembled from at least a main connector and a sub-connector.
To achieve the above and other objects, the sectional connector of the present invention mainly includes a main connector having pins in two rows, one or more first sub-connector having pins in one row, and a second sub-connector having pins in one row, sequentially connected through engagement of dovetail grooves and dovetail tenons correspondingly provided on side surfaces of the main connector and the sub-connectors in contact with one another. The sectional connector may substitute for PC104 and PC104 PLUS industrial computer connectors having pins in 2+2 rows and pins in 2+2+4 rows, respectively, for connecting buses. Number of the first sub-connectors used in forming the sectional connector may be changed, depending on actual need in designing an industrial computer. The sectional connector enables easy and firm connecting and soldering of pins to a PC board row by row.